Octave V 70 Class A, Руководство пользователя

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7. TUBES
7.4 Replacing the tubes

Driver tubes
Replacement driver tubes require no adjustment.

Output tubes
General procedure
1.

Switch off the amplifier and allow it to cool down for 10 minutes. Remove
the old tubes and fit the new ones.
2. Before switching the V 70 Class A on again with new tubes: make sure that
the tubes are correctly inserted and that the correct types are used in the
corresponding positions 5, 6 and 7 in the case of the driver tubes.
3.
Switch on the amplifier and turn the mode selector switch (No. [2] ) to the
BIAS position. Following the Soft-Start phase, all 4 "minus" LEDs (yellow)
will illuminate. If from this point of time any of the LEDs are green or red,
this indicates a faulty tube that must be replaced.
If all tubes are ok, the BIAS display will change to green after approx.
2 minutes
.
3.1
Original Octave tubes.
There is no need to burn in original Octave replacement tubes. Allow
the tubes 10 minutes to warm up and adjust them to the appropriate
setting for the tube type
3.2
New, untested output tubes should be allowed a longer warm up period.
You should check these tubes after about 20 minutes
7.5 Running in the tubes
All OCTAVE equipment is subject to a 48-hour Long-term quality test at the factory to burn in the
tubes. The tubes are preselected for use in each particular model.
New tubes can take up to three months to run in and start sounding their best.
Daily use is beneficial in speeding up this process but is not mandatory. Continuous operation does
very little to help reduce the running-in time and is therefore
not
recommended.
7.6 Tube Service Life

Thanks to the protection circuits and soft-start electronics, the output tubes in your amplifier
should achieve a service life of up to 3 - 5 years.

Driver tubes can be used for 10 years or even longer.

Because tubes have different service lives, you will never have to renew the entire tube
complement at the same time. The power tubes should be replaced in pairs (V1.2 and 3.4) if a
power tube of the power amplifier pairs has to be replaced

Some tubes require a long time (up to 300 hours) to achieve their optimum sound quality.
Depending on how long the tubes have been stored, it may be necessary to adjust the BIAS
several times in the first two to three weeks after installing them.